body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
}

nav {
    background-color: #333;
    color: white;
}

nav ul {
    list-style-type: none;
    margin: 0;
    padding: 0;
    display: flex;
    justify-content: space-around;
}

nav ul li {
    padding: 15px;
}

nav ul li a {
    color: white;
    text-decoration: none;
}

h1 {
    text-align: center;
    margin-top: 20px;
}

.info-section,
.operation-section {
    border: 1px solid #ccc;
    padding: 20px;
    margin: 20px;
}

table {
    width: 80%;
    margin: 20px auto;
    border-collapse: collapse;
}

table,
th,
td {
    border: 1px solid #ccc;
}

th,
td {
    padding: 10px;
    text-align: center;
}

form {
    width: 50%;
    margin: 20px auto;
    border: 1px solid #ccc;
    padding: 20px;
}

form label {
    display: block;
    margin-bottom: 5px;
}

form input {
    width: 100%;
    padding: 10px;
    margin-bottom: 15px;
}

button {
    padding: 10px 20px;
    background-color: #333;
    color: white;
    border: none;
    cursor: pointer;
}

button:hover {
    background-color: #555;
}